Cuckoo: a wackadoo horror-thriller that promises more than it delivers

Screening at the Berlin Film Festival, Tilman Singer’s chiller has an intriguing premise but keeps missing the target

Cuckoo wants so badly to be a midnight movie, it wears itself out. Exuding more uncertainty than discipline, this wackadoo horror-thriller from German writer-director Tilman Singer can’t decide if wearing a smirk will see it through a sloppily developed plot, which keeps promising more than it delivers. With another redraft, a tauter edit, it might have snapped into focus.
What fun there is to be had comes from puzzling out the concept – and from Dan Stevens, who puts on a comical German accent, clearly enjoying himself as Herr König, the sinister proprietor of a barely populated resort hotel in the Alps.
Here a sullen 17-year-old called Gretchen (Euphoria’s Hunter Schafer), who has recently lost her mother, is dragged by her father (Marton Csokas) and new stepmother (Jessica Henwick) as the film starts. Her general air of angsty discontent is not about to be salved by the freaky goings-on.
There’s something – or things – running around in the woods at night, emitting wild noises that may or may not be causing the guests to throw up. It takes human, or at least humanoid, form, and we soon deduce that Herr König has charge of it in some way, not least when he pulls out a small wooden flute and plays a beckoning note in the hotel grounds. 
This Hammer horror touch is of a piece with everything Stevens does in this part. As he has proved before (in The Guest and The Rental), he’s a real asset in trashy genre fare, and a hoot as a villain: his particular pronunciation of the name “Gretchen” here – as if it had an acute accent on the first “e” – never gets less funny.
To detail the film’s experiments would stray into spoilerville, but for most of the middle act, Gretchen is the only one aware of something up: twice, she’s hospitalised after close scrapes with this marauding creature, and her parents are too preoccupied with the behavioural problems of her younger stepsister Alma (Mila Lieu), who doesn’t speak, to heed her concerns.
Schafer, who has the angry verve of a young Milla Jovovich, does a sharp job keeping us on side. But the generational conflict here feels by-the-book, and the parents, as characters, are surplus to requirements. The film’s weakest scene is a heart-to-heart in sign language between the sisters – because it’s so poorly timed, right in the thick of a gory third act, with armed antagonists breathing down their necks.
Cuckoo winds up owing a fair bit to early David Cronenberg – especially The Brood (1979) – but settles for slapdash mayhem, and some odd moments of looping footage (like record scratches) when the action heats up. Instead of having the disorienting effect Singer intends, these feel like testing out a gimmick on us. Mileage will vary, but it’s possible to respond to the whole film like a lab rat that would rather opt out.
Cert 15, 102 min. In cinemas